A provision of assemblies and methods for treating exhaust gases from combustion devices to reduce air contaminants in the exhaust gas. The exhaust from a combustion device is cooled, followed by passing the exhaust through first and second catalytic chambers with an oxygen enrichment means in between the catalytic chambers. The catalytic chambers comprise at least one catalyst that substantially reduces nitrogen oxides or carbon monoxide or both.

Various methods are provided for managing a fuel system of a vehicle. In one example, the method may include enclosing, at least partially, a gaseous fuel delivery, storage, and/or consumption element of the vehicle. The method may include sensing an indication of gaseous fuel in an unintended region and generating an alert and/or adjusting an actuator in response to the sensed gaseous fuel above a threshold.

A method for controlling an internal combustion engine operating on at least partly gaseous fuel is disclosed. The method may include providing a desired burn rate profile corresponding to a desired operation of the internal combustion engine. The method may further include selecting first operating parameters such that an operation of the internal combustion engine with a first gas composition produces a first burn rate profile that corresponds to the desired burn rate profile. The method may also include operating the internal combustion engine with the first operating parameters using a second gas composition. The method may include determining that the second burn rate profile differs from the desired burn rate profile. In addition, the method may include adjusting an operating parameter from among the first operating parameters of the internal combustion engine to approach the desired burn rate profile.

Various methods and systems are provided for an intake manifold for an engine. In one example, an insert comprises an annular body having a top surface, bottom surface, inner surface, and outer surface. The insert further comprises a first groove for coupling an intake air port of an intake manifold to a cylinder head, a second groove for circulating gaseous fuel received from a gas runner of the intake manifold, and one or more openings to fluidically couple the second groove to an interior of the intake air port. The insert is configured to mix gaseous fuel and intake air at a coupling location between the intake manifold and the cylinder head.

Methods and systems are provided for a multi-fuel engine. In one example, a method includes adjusting a substitution ratio based on an intake manifold temperature. The method further including adjusting the intake manifold temperature to increase the substitution ratio.

The invented system adds some petrol fuel to the vehicle engine which runs with natural gas (CNG or LPG). It causes a simultaneous combustion of petrol and natural gas (CNG or LPG). This action decreases depreciation of engine, increases power of the engine and reduces fuel consumption in natural gas vehicles. The above-mentioned system consists of an innovative petrol holder storage, an electronically circuit, a relay, a lever micro switch and a petrol fuel injector. Whenever the accelerator pedal is pressed more than a certain amount, the system will be activated and command to inject petrol collected in the storage into the air manifold.

Methods and systems are provided for adjusting a location of a fuel injection in response to a substitution rate and a desired EGR flow. In one example, a method may include injecting a first fuel to a combustion chamber via a direct injector positioned to inject directly into the combustion chamber, injecting a second, different, fuel to the combustion chamber via an exhaust port injector positioned to inject toward an exhaust valve of the combustion chamber, and combusting the first and second fuels together in the combustion chamber.

The present invention relates to a method for controlling injection of a gaseous fuel, such as hydrogen or a hydrogen based gas, and a water-based fluid medium into a combustion engine. The method comprises the steps of: in a first operational mode injecting the gaseous fuel and optionally a water based fluid medium into a combustion chamber of the engine at a relatively high pressure; in a second operational mode injecting water as liquid into engine to reduce the temperature and pressure inside the combustion chamber, and injecting the gaseous fuel into the combustion chamber at a relatively low pressure.

A method for operating an oxycombustion engine system includes passing a nitrogen-depleted gas, a fuel, and a recycled exhaust gas into a combustion chamber, combusting a mixture of the nitrogen-depleted gas, the fuel, and the recycled exhaust gas, thereby producing an exhaust gas including carbon dioxide, detecting a pressure of the recycled exhaust gas passed to the combustion chamber, determining whether the detected pressure of the recycled exhaust gas is less than a configurable pressure threshold, and in response to determining that the detected pressure of the recycled exhaust gas is less than the configurable pressure threshold, increasing the pressure of the recycled exhaust gas passed to the combustion chamber.

The present invention discloses a method of introducing fuel into a diesel engine for combustion within the engine. A natural gas in liquid form is injected into the engine for combustion therein with diesel fuel so as to maintain a natural gas concentration derived from the liquid in the range of greater than 0.6% to 3.0% of air intake by volume of natural gas. Suitable gases include natural gas, methane or substantially methane gas mixtures and substitute natural gas such as propane air mixtures providing a mixture with similar combustion properties to methane/natural gas.